UIPinchGestureRecognizer inwards pinch "slower" - ios

Question

I'm using UIPinchGestureRecognizer in my app to zoom in on a view (and yes, there's a reason I'm not using UIScrollView). When I pinch outwards with my fingers, the view zooms in as expected, and if I then reverse pinch without taking my fingers off the screen, it also zooms right. However, if I initiate the zoom by pinching inwards, the rate at which the view zooms is dramatically slower. I'm guessing this is because of how UIPinchGestureRecognizer works - the scale of the UIPinchGestureRecognizer is >1 when pinching outwards, and <1 when pinching inwards. Unfortunately, I do not know how to accurately reflect this in my code.
- (IBAction)didDetectPinchGesture:(id)sender {
UIPinchGestureRecognizer *gestureRecognizer = (UIPinchGestureRecognizer *)sender;
CGFloat scale = [gestureRecognizer scale];
switch ([gestureRecognizer state]) {
case UIGestureRecognizerStateBegan:
_lastScale = [gestureRecognizer scale];
break;
case UIGestureRecognizerStateChanged:
CGFloat currentScale = [[self.imageView.layer valueForKeyPath:#"transform.scale"] floatValue];
// Constants to adjust the max/min values of zoom
const CGFloat kMaxScale = 5.0;
const CGFloat kMinScale = 1.0;
CGFloat newScale = 1 - (_lastScale - scale); // new scale is in the range (0-1)
newScale = MIN(newScale, kMaxScale / currentScale);
newScale = MAX(newScale, kMinScale / currentScale);
NSLog(#"%f", newScale);
CGAffineTransform transform = CGAffineTransformScale([self.imageView transform], newScale, newScale);
self.imageView.transform = transform;
_lastScale = scale; // Store the previous scale factor for the next pinch gesture call
break;
default:
_lastScale = [gestureRecognizer scale];
break;
}
}

Answer 1

A very simple solution to this is to reset the gestureRecognizer scale back to 1 when you're finished:
...
default:
_lastScale = [gestureRecognizer scale];
// Add this:
[gestureRecognizer setScale:1];
break;
}